Line devices exist that attach to power lines in order to measure various electrical parameters of the power line. Known devices, such as the power donuts described in U.S. Pat. No. 4,746,241 issued to Burbank, include a donut-shaped outer housing with an inner hub of a fixed size that connects to a single size or diameter of power line. In order for the power donut to operate in conjunction with a different size power line, one must change out the inner hub, which may be a time-consuming process when many power donuts need to be changed. Further, the installer must bear the full weight of the power-donut during installation and removal, which takes place at the end of a long rod known as a “hot stick” in the industry. Accordingly, there is a need for a line device that does not suffer from these problems.